1. Field of the Invention
The present invention relates to a symbol selector and a symbol selection method for inputting a symbol and more specifically to a symbol selector and a symbol selection method for selecting a predetermined symbol from a predetermined list.
2. Description of the Related Art
In general, characters are inputted conventionally to information processing apparatuses by keyboards. However, a keyboard occupies a relatively large area and is therefore not handy to carry. Hence, a method has been adopted to reduce the area of the symbol selector of a keyboard by reducing the number of keys. For example, in a character input method that has been widely used, plural characters are assigned to each numerical key, so that the assigned characters show up in turns by pressing a key repeatedly plural times.
However, in this method it is difficult to understand intuitively to which of the numerical keys a desired character is assigned and how many times the numerical key needs to be pressed to select the desired character. This causes a problem in that users have to be accustomed to these factors.
In another kind of technique, selection of characters as described above is achieved independently from key manipulation. For example, an acceleration detector which detects physical motion effected externally on a terminal is provided, and a trace of the motion effected on the terminal is obtained based on a detection output from the acceleration detector. The trace of the motion is displayed on a display unit. If the acceleration detector detects that further motion to fix the trace is effected on the terminal with the trace displayed, the trace of the former motion is recognized as an inputted character (see Jpn. Pat. Appln. Laid-Open Publication No. 2002-169645.
In this method, however, if the acceleration detector has a low detection sensitivity to acceleration, physical motion effected externally cannot be accurately grasped. Therefore, the motion trace cannot be drawn based on the motion. As a result, another problem arises in that a very long time is needed until an arbitrary character is inputted. On the contrary, if the detection sensitivity of the acceleration detector is high, physical vibration that a user unintentionally makes is detected with oversensitivity, and a wrong motion trace is drawn. As a result, a very long time is needed until an arbitrary character is inputted, too.
There also is a method of using a pen-type manipulator to compensate for the drawbacks of the key input method. For example, a desired character is selected from a displayed list having a keyboard-like appearance on a display unit by touching the list with a pen. Alternatively, the trace of motion of a pen is detected, and features of a character are detected from the detection result, to achieve character recognition (see Jpn. Pat. Publication 3,045,891). The character recognition of this kind requires highly advanced hardware and software, and it is difficult to lower the price of a device of this kind. In addition, erroneous character recognition occurs frequently. This kind of character recognition is not always easy to use.